1. Field of the Invention
The present invention is generally concerned with clutch release berings, for automotive vehicles in particular.
It is more particularly directed to clutch release berings of the so-called "pull" type which are designed to act in traction on the clutch release device of the clutch to be controlled and which, for this purpose, must be coupled to the latter.
2. Description of the Prior Art
In certain clutch release bearing assemblies, and in particular in the clutch release bearing assembly described in French patent application No. 83 05848 filed Apr. 11 1983, it has been proposed to employ for this purpose, disposed between the clutch release bearing and the clutch release device to be controlled, a member which is referred to hereinafter for convenience as the "coupling member" (or "actuator member") which, appropriately attached to said clutch release device, comprises a radial bearing flange on the side of the latter opposite the clutch release bearing, by means of which it is adapted to act thereon, in cooperation with attachment means acting in traction which, disposed between a coupling member of this kind and a member referred to hereinafter for convenience as the "drive member", forming part of the clutch release bearing, are adapted to provide an axial linkage between said members in the axial direction from the clutch release device to said clutch release bearing.
In practice, in French patent application No. 83 05848 mentioned hereinabove, the attachment means acting in traction which are employed consist generally of a coupling member which is elastically deformable in the radial direction and which is carried by one of the members to be coupled together in traction, being designed to cooperate abutment fashion with a driving bearing surface formed generally transversely to this end on the other of these members.
A notable advantage of an arrangement of this kind is that it permits the clutch release device of the clutch to be controlled to be fitted in advance with the coupling member, even before the corresponding clutch cover assembly is assembled, engagement being completed on subsequent asssembly by simple snap-fastener attachment of the clutch release bearing to said coupling member.
In certain of the embodiments proposed in French patent application No. 83 05848 mentioned hereinabove, the elastically deformable coupling member employed is an annual member which has oblique fingers elastically deformable in the radial direction.
Although satisfactory, a coupling member of this kind has the disadvantage of being relatively costly and of requiring a non-negligible force for fitting it.
In other embodiments described in French patent application No. 83 05848 mentioned hereinabove, the coupling member is a ring, referred to hereinafter for convenience as the "coupling ring", which is at least partially engaged in the radial direction in an annular retaining groove provided for it on one of the members to be attached together in traction, the other of these members featuring the driving bearing surface with which it must cooperate for such fastening.
The coupling ring thus employed may, for example, consist of a split ring of circular transverse cross-section featuring spaced and alternating rectilinear sections through which it is engaged without clearance with the bottom of a retaining groove in which it is inserted, at points on a circle of relatively small radius, and part-circular sections of relatively larger radius, through which it is adapted to cooperate with the corresponding driving bearing surface.
As an alternative, the coupling ring employed may consist of a simple split elastic ring of circular contour and rectangular transverse cross-section, engaged with play in the associated retaining groove.
To reduce the disadvantages inherent in this type of assembly, which will not be explained in detail herein, French patent application No. 83 05848 filed Apr. 11 1983 proposes a simplified release bearing assembly of the same type, providing for the use of a coupling ring of circular transverse cross-section and further providing for snap-fastener type attachment which may be effected in a reliable manner without possibility of misoperation or mistake.
According to this application, that of the flanks of the retaining groove which is on the opposite side of the driving bearing surface to the coupling ring, in the axial direction, is generally oblique to the axis of the assembly, diverging from the other flank of said retaining groove in the direction away from said axis.
Thus in service, that is to say when the drive member of the clutch release bearing is exerting traction on the coupling member, and on the clutch release device of the clutch to be controlled through the intermediary of the latter, the coupling ring operating axially between said members is systematically urged in the direction towards the driving bearing surface with which it must cooperate, so that the amount of room the latter takes up on the relevant member may be relatively small without it being necessary for this purpose to confer a special configuration on said coupling ring.
The release bearing assemblies outlined hereinabove using a coupling ring engaged in a groove formed either in the coupling member or in the drive member are certainly satisfactory with regard to the transmission of traction from the clutch release bearing to the clutch release device of the clutch cover assembly and with regard to facilitating fitting of the clutch release bearing to the clutch cover assembly, effected by a simple clipping action.
However, in these release bearing assemblies, it is not possible to decouple the clutch release bearing from the coupling member except by operating on the coupling ring so as to force it again into the retaining groove, for example using a tool inserted for this purpose between the drive member and the coupling member, from the side of the latter opposite the clutch release bearing, which often involves first unbolting the clutch cover assembly from the flywheel carried by the motor. In many cases it is not possible to provide access for a tool and it is desirable to be able to effect this decoupling, that is to say, in the final analysis, to decouple the motor from the gearbox, without proceeding to remove the clutch cover assembly. On the contrary, and for all the reasons mentioned hereinabove, it is desirable to retain the release bearing assembly by a simple clipping action using a coupling ring engaged in a retaining groove.
The present invention is directed towards an arrangement with which this objective may be achieved, in a simple manner and without significantly increasing the production cost of the clutch release bearing assembly.